Organic fertilizer is a key input for green agriculture. Granulated organic fertilizer production can effectively improve fertilizer efficiency, reduce dust pollution, and facilitate mechanized application. Fertilizer granulation is a key step in organic fertilizer production line, directly affecting the granule’s strength, solubility, and commercial value. This article systematically introduces the key processes in organic fertilizer granulation production.

1.Raw material pretreatment

Organic fertilizer raw materials usually include livestock and poultry manure, straw, mushroom residue, kitchen waste, etc. The characteristics of organic fertilizer raw materials are high moisture content, high fiber content, and varying viscosity. The pretreatment steps include:

Fermentation and Maturation: Compost turning machines, such as chain compost turning machine and windrow compost turning machine, utilize microorganisms to degrade organic matter, eliminate pathogens and weed seeds, and reduce moisture to an appropriate range.

Grinding and Screening: A half-wet material crusher is used to process fiber raw materials to ensure particle fineness and prevent clogging of pelletizer dies.

2.Fertilizer granulator

Rotary drum Granulator: Mixed materials enter a rotating drum where they roll and agglomerate under the action of centrifugal force and a binder, gradually forming spherical granules.The advantage of the rotary drum granulator is that the finished fertilizer granules are beautiful and suitable for large-scale production.

Disc granulator: The tilted rotating disc causes the powder to continuously roll and adhere, forming uniform granules. Particle size can be controlled by adjusting the disc’s tilt angle and rotation speed.The advantages of the disc granulator are that the diameter of the fertilizer particles can be controlled, the operation is simple, and it is suitable for small-scale production.

Double roller press granulator: High pressure forces powder through a die to form spherical granules. This granulator is suitable for low-moisture materials and produces high granule density.The advantage of the double roller press machine is that it can be produced without drying and the fertilizer particles have high density.

3.Post-processing

After the fertilizer is granulated, the moisture content of the fertilizer particles needs to be strictly controlled. A fertilizer dryer and a fertilizer cooler need to be used to control the moisture in the fertilizer.

Nowadays, organic agriculture is being promoted continuously. Organic fertilizer granulation is a key step in increasing product added value. Reasonable selection of fertilizer granulator and process parameters can take into account both efficiency and quality.